Agenda - Council - 06/14/2005 - Laserfiche WebLink

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topsoil re-spread, turf establishment, silt fences, rock construction entrance and erosion control mats or wood fiber blankets. BMPs will be implemented as soon as possible to mitigate erosion and sediment, which is required for all land disturbances. Land disturbing activities shall occur in increments so that adequate BMP control can be provided throughout all phases of construction. In all areas outside of the construction area, the existing vegetation shall be preserved to provide a permanent vegetative cover. Silt fences will be installed down gradient from construction areas and wherever runoff from the construction area discharges from the site. Grading will be · minimized in wooded areas and slopes will be flattened in graded areas as much as possible to prevent erosion and sediment deposits. The desi~,m of the site will reserve some open space adjacent to sensitive wetland areas. Wooded areas along the wetland will be preserved, where possible, to provide wildlife habitat area and to protect the wetland. Street widths, setbacks, and building types are designed to minimize their impact on the environmentally sensitive areas of the site. As part of the platting process, an Erosion and S. ediment Control Plan and a Storm Water Pollution Prevention Plan (SWPPP) will be submitted for review and approval. The developer must also obtain and comply with National Polhttant Discharge Elimination System (NPDES) permit requirements, including the SWPPP. There are no steep slopes on the site. According to the Soil Survey of Anoka County, soils on the site are Rf(Rifle mucky peat), AhA (Anoka loamy fine sand, 0 to 2 percent slopes), AnB (Anoka loamy fine sand, 2.to 6 percent slopes), AnC (Anoka loamy fine sand, 6 to 12 percent slopes), LnA (Line loamy fine safid, 0 to 4 percent slopes), ZmA (Zimmerman fine sand, 0 to 2 percent slopes), ZmB (Zimmerman fine sand, 2 to 6 pement slopes), ZmD (Zimmerman fine sand, 6 to 12 percent slopes), and DIA (Dalbo silt loam, 1 to 5 percent slopes). The distribution of these soil types is shown in Figure 4. There are potentially highly credible soils on the site: AnC (Anoka loamy fine sand, 6 to 12 percent slopes) and DIA (Dalbo silt loam, I to 5 percent slopes), which is considered not highly credible based on typical slope percentages and length for determinations made in the NRCS office. ZmD (Zim~nerman fine sand, 6 to 12 percent slopes) is also a potentially highly credible soil, which is considered to be highly credible based on typical slope percentage and length for determinations made in the NRCS office. Soil inspection and compaction testing by a licensed engineer will be conducted on all lots where filling is required, in accordance with the approved grading plan. Soil stabilization will be employed throughout the plat on an as needed basis as determined by the City of Ramsey to ensure the integrity of the soils. a. Compare the quantity and quality of site runoff before and after the project. Describe permanent controls to manage or treat runoff. Describe any stormwater pollution prevention plans. The proposed discharge will be collected into a storm water management system pribr to.being discharged at or below existing flow rates into the wetlands and ditches on site. The wetlands and ditches empty into Trott Brook, and then into the Rum River, a tributary of the Mississippi River. A Storm Water Pollution Prevention Plan will be created and implemented as part of the improvements process. Temporary sediment and erosion control measures will utiltize various BMPs during the construction of the improvements, and permanent features such as detention ponds and grassed swales will be used for flow rate control and water quality purposes. Excavation of pending areas on the site will provide sedimentation and rate control for storm water generated by this development. The runoff will be managed by directing the street runoff to combination sediment/retention basins excavated in upland areas or the site. From the pending areas, the runoff will be directed to the existing and created wetlands located throughout the site. These wetlands will allow the water to drain to the existing ditches within the site. b. Identify routes and receiving water bodies for runoff from the site; include major downstream water bodies as well as the i-mmediate receiving waters. Estimate impact runoff on the quality of receiving waters. 'File treated runoff from the site will enter the Wetlands and ditches w'it"hln the site, and into Trott Brook. The wetlands and ditches ultimate, l?empty into the Rum River, a tributary of the Mississippi River. Although the w)lume of storm water entering the Rum River may indreasel the rate at wh'i~h it is discharged will not exceed current pre-developed rates. There are no adverse impacts anticipated with the proposed development improvements. .,.,